CN113751570B - Titanium alloy four-layer structure forming die, die assembly and preparation method - Google Patents
Titanium alloy four-layer structure forming die, die assembly and preparation method Download PDFInfo
- Publication number
- CN113751570B CN113751570B CN202111083106.9A CN202111083106A CN113751570B CN 113751570 B CN113751570 B CN 113751570B CN 202111083106 A CN202111083106 A CN 202111083106A CN 113751570 B CN113751570 B CN 113751570B
- Authority
- CN
- China
- Prior art keywords
- skin
- forming
- core layer
- die
- plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
- B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
- B21D26/053—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure characterised by the material of the blanks
- B21D26/055—Blanks having super-plastic properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/10—Die sets; Pillar guides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/16—Heating or cooling
Abstract
The invention relates to a high-temperature forming flexible die, a die assembly and a preparation method for a titanium alloy four-layer structure, belongs to the technical field of superplastic forming, and is used for solving the problem that a skin has a groove in the forming process of the titanium alloy four-layer structure, wherein the die comprises: a movable forming plate; the movable forming plate is provided with punches, buffer grooves are arranged among the punches, and the punches correspond to the core layer rib grids of the titanium alloy four-layer structure one by one. The technical scheme provided by the invention can eliminate the groove on the skin in the forming process.
Description
Technical Field
The invention belongs to the technical field of superplastic forming, and particularly relates to a high-temperature forming flexible mold and a mold assembly for a titanium alloy four-layer structure and a preparation method of the flexible mold and the mold assembly.
Background
In the process of forming the stud by superplastic forming of the core layer in the four-layer structure product, the core layer and the skin can be contacted in advance and are in diffusion connection, the skin is very easy to receive inward compressive stress at the stud, and if the friction force between the skin and the mold is insufficient, the groove defect is very easy to appear on the surface of the skin, so that the use performance is influenced.
The current forms of the surface grooves of the control skin are as follows: (1) the mode of thickening the skin or wrapping is adopted, and the mode essentially increases the integral thickness of the skin to increase the deformation resistance, so the operation of removing the allowance is added after the forming is finished; (2) the back pressure is applied between the skin and the core layer, and the back pressure is applied inside the skin and the core layer, so that the friction between the skin and the mold can be increased, and the compressive stress in the skin can be reduced, but the method can only reduce the generation of grooves to a certain extent.
Disclosure of Invention
In view of the above analysis, the present invention is directed to a titanium alloy four-layer high-temperature forming flexible mold, a mold assembly and a manufacturing method thereof, so as to solve at least one of the above technical problems.
The purpose of the invention is mainly realized by the following technical scheme:
in a first aspect, an embodiment of the present invention provides a titanium alloy four-layer structure high-temperature forming flexible mold, which is characterized by including: a movable forming plate;
the movable forming plate is provided with punches, buffer grooves are arranged among the punches, and the punches correspond to the core layer rib grids of the titanium alloy four-layer structure one by one.
Further, the mold further comprises: a pressure plate, a spring and a fixed forming plate;
the fixed forming plate and the pressing plate form a closed chamber;
said movable forming plate being mounted on said fixed forming plate, said movable forming plate being movable relative to said fixed forming plate;
and in the closed chamber, one end of the spring is connected with the pressure plate, and the other end of the spring is connected with the movable forming plate.
Further, the mold further comprises: a stopper;
the locating part is arranged in the closed cavity and is arranged between the pressure plate and the movable forming plate.
Further, the stopper comprises a first size and a second size;
when the limiting piece limits the movable forming plate to move by the first size, the mould is used for preforming the skin of the titanium alloy four-layer structure;
when the limiting piece limits the movable forming plate to move in the second size, the die is used for preparing the titanium alloy four-layer structure.
In a second aspect, an embodiment of the present invention provides a mold assembly, including: an upper forming die;
the upper forming die is the die of the first aspect.
Further, the mold assembly further comprises: a lower forming die;
the lower forming die is the die according to any one of the first aspect.
In a third aspect, an embodiment of the present invention provides a method for preparing a titanium alloy four-layer structure, where the mold assembly according to the second aspect includes:
step 1, selecting plates for high-temperature forming of a four-layer structure, namely an upper skin, a lower skin, an upper core layer and a lower core layer;
step 2, performing the upper skin and the lower skin respectively by using a lower forming die to obtain a preformed upper skin and a preformed lower skin;
step 4, placing the component into a space formed by an upper forming die and a lower forming die, wherein the preformed upper skin is abutted with a punch of the upper forming die, and the preformed lower skin is abutted with a punch of the lower forming die;
Further, ribs are respectively arranged on the upper skin and the lower skin, and solder resist is smeared on the ribs;
the ribs correspond to gaps among the ribs of the core layer.
Further, a first vent pipeline is arranged between the upper skin and the upper core layer;
a second vent line is arranged between the upper core layer and the lower core layer;
and a third air through pipeline is arranged between the lower core layer and the lower skin.
Further, after the whole body is heated to the diffusion connection temperature, pressure is applied to the first vent pipeline and the third vent pipeline and heat is preserved, so that the upper core layer and the lower core layer are tightly attached; after the upper core layer and the lower core layer are in diffusion connection, integrally heating to a superplastic forming temperature, and continuously applying air pressure to a second air passage; the whole is used to indicate the upper skin, the upper core layer, the lower core layer, the preformed lower skin.
Further, after step 2, a sealing welding is also included before step 3.
Further, welding the upper core layer and the lower core layer together, and welding a second vent pipeline at the position of the air inlet; and welding the upper skin, the lower skin, the sealed upper core layer and the sealed lower core layer together, welding a first ventilation pipeline between the upper skin and the upper core layer, and welding a third ventilation pipeline between the lower skin and the lower core layer.
Further, in step 5, the limiting member of the lower forming mold is adjusted to the titanium alloy four-layer structure preparation state, and then the upper forming mold and the lower forming mold are mounted on the hot forming machine.
Furthermore, the pressure applied to the first ventilation pipeline and the third ventilation pipeline is 0.1MPa, and the temperature is kept for 2 h.
Compared with the prior art, the invention can at least realize one of the following technical effects:
1. during the superplastic forming process, as shown in fig. 1, the upper (lower) core layer rib grids extrude the upper (lower) skin under the action of air pressure P1. And the pressure of the air between the ribs of the upper (lower) core layer on the upper (lower) skin is P2. The punches correspond to the core rib grids one by one, so that the punches and skins on the punches bear the pressure P1, and the punches move under the action of the pressure P1. The skin at the buffer groove bears the pressure P2, and forms a protrusion along the inner wall of the buffer groove under the action of P2 and back stress F, and a groove is formed on the surface of the skin. Typically, the size of the protrusion is determined by the back stress F. However, the back stress F is not sufficient to allow the size of the protrusion to continue to increase due to the presence of the buffer groove, thereby enabling the formation of an eliminable groove in the skin surface. Then, the punch is pushed by P1, so that the skins on both sides of the protruding part continue to move downwards, and the purpose of flattening the skins is achieved.
2. And the growth space of the rib grids of the core layer is increased by performing the skin, so that the time for the skin to have the grooves is prolonged. After time delay, the stress of the P2 and the back of the skin is stable, and the groove which can be eliminated is easier to generate.
3. The limiting piece is arranged in the die to control the movable forming plate to have at least two maximum displacement amounts in the closed cavity, and each maximum displacement amount corresponds to one function, so that the die has multiple purposes, and the process equipment is simplified.
4. And coating a solder resist on the ribs of the skin to prevent the core layer ribs from being in diffusion connection with the ribs on the skin before contacting the skin.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and drawings.
Drawings
The drawings, in which like reference numerals refer to like parts throughout, are for the purpose of illustrating particular embodiments only and are not to be considered limiting of the invention.
FIG. 1 is a partial schematic view of a superplastic forming process provided by an embodiment of the present invention;
FIG. 2 is a schematic diagram of upper and lower core solder resist coating locations provided by an embodiment of the present invention;
FIG. 3 is a schematic structural diagram of a high-temperature forming flexible mold with a titanium alloy four-layer structure according to an embodiment of the present invention;
FIG. 4 is a schematic structural diagram of another titanium alloy four-layer structure high-temperature forming flexible mold according to an embodiment of the present invention;
fig. 5 is a schematic diagram illustrating a first dimension of a limiting element according to an embodiment of the invention;
fig. 6 is a schematic diagram illustrating a second dimension of a limiting element according to an embodiment of the invention;
fig. 7 is a schematic view of a hot press forming die provided in an embodiment of the present invention in an operating state;
FIG. 8 is a schematic view of a vent line according to an embodiment of the present invention;
fig. 9 is a schematic structural diagram of a formed product according to an embodiment of the present invention.
Reference numerals:
1-pressing a plate; 2-countersunk head screw; 3-a spring; 4-fixing the forming plate; 5-a movable forming plate; 51-a punch; 52-a buffer tank; 6-a limiting part; x-a first vent line; y-a second vent line; z-a third ventilation line.
Detailed Description
The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form a part hereof, and which together with the embodiments of the invention serve to explain the principles of the invention and not to limit its scope.
The most widely applied superplastic forming technology is a superplastic forming/diffusion bonding combined process technology combined with a diffusion bonding technology, and an integral component with a space sandwich structure is formed at one time by utilizing the characteristic that a metal material has superplasticity and diffusion bonding property in a temperature range. The forming component can be divided into a single-layer structure, a two-layer structure, a three-layer structure and a four-layer structure according to different initial blank numbers of the forming components.
Aiming at the four-layer structure, the structure sequentially comprises the following components from top to bottom: the skin structure comprises an upper skin, an upper core layer, a lower core layer and a lower skin. A semi-closed "pouch" is formed with the upper core and the lower core prior to forming and is placed between the upper and lower skins. And then arranging the four-layer structure in a mould, and heating until the core layer material reaches a superplastic state. And finally, applying pressure to the interior of the bag to expand the bag and extrude the upper skin and the lower skin, and finally enabling the upper skin and the lower skin to be tightly attached to the inner wall of the mould, thereby completing the forming process.
In the actual process, parts of the bag are welded together by welding, as shown in fig. 2, the shaded areas are areas where the upper and lower core layers are welded, and the white areas are coated with solder resist, so that only the white areas grow under pressure, and the white areas grow to form the core rib grids. The structure of the formed product is shown in fig. 9. When the skin is extruded by the core layer crystal lattices, the skin among the core layer crystal lattices is extruded in two directions to easily form grooves on the surface, and the grooves can influence the performance of the device.
In order to solve the above technical problem, an embodiment of the present invention provides a titanium alloy four-layer structure high-temperature forming flexible mold, as shown in fig. 3, including: a press plate 1, a countersunk screw 2, a spring 3, a fixed forming plate 4 and a movable forming plate 5.
The fixed forming plate 4 is connected to the press plate 1 to form a chamber, the moving side of the movable forming plate 5 is located in the chamber, and the forming side of the movable forming plate 5 is provided with punches 51 and buffer grooves 52 alternately distributed.
The springs are arranged between the moving side of the movable forming plate 5 and the press plate, i.e. the springs 3 are connected to the press plate 1 at one end and to the movable forming plate 5 at one end.
The invention solves the problem that when the skin is extruded by the crystal lattices of the core layer, the skin among the crystal lattices of the core layer is extruded in two directions to form grooves on the surface easily through the structural arrangement of the movable forming plate.
Specifically, one end of the fixed forming plate 4 is connected with the pressure plate 1 and fixed by the countersunk head screw 2. The other end of the fixed forming plate 4 forms a butt joint surface of an upper forming die and a lower forming die, and the forming side end surface of the movable forming plate 5 is not flush with the butt joint surface of the fixed forming plate 4, so that a containing forming space of a four-layer structure of an upper skin, an upper core layer, a lower core layer and a lower skin is formed conveniently, and the shape of the space is matched with that of the buckled upper skin and the buckled lower skin.
Specifically, the movable forming plate 5 is movable in a layer direction relative to the fixed forming plate 4, and in order to facilitate the movement of the movable forming plate 5 in the cavity, a stepped hole may be provided on the abutting surface side of the fixed forming plate 4, so that the punch 51 and the buffer groove 52 pass through the stepped hole, and the moving side of the movable forming plate 5 is overlapped on the limit step, thereby realizing the limit and fixation of the movable forming plate 5.
Illustratively, the fixed forming plate 4 is a stepped-bore cylindrical structure having a small-diameter section and a large-diameter section, and the movable forming plate 5 is piston-shaped and includes a head end and a rod end, the head end having a diameter larger than that of the rod end, and the rod end being provided with alternately arranged punches 51 and buffer grooves 52.
In an initial state, the head end of the movable forming plate 5 is lapped on the step surface, the rod end penetrates through the small-diameter section, the spring is in a natural telescopic state, or one end of the spring abuts against the head end of the movable forming plate 5.
During the forming process, under the combined action of the forming pressure and the spring, the head end of the movable forming plate 5 moves along the cylinder wall of the large-diameter section of the fixed forming plate 4, and the rod end moves together, wholly or partially, to the large-diameter section of the fixed forming plate 4.
Specifically, the movable forming plate 5 is provided with punches 51, buffer grooves 52 are provided between the punches 51, and the punches 51 correspond to the core ribs one by one. The size of the buffer groove depends on the distance between the ribs of the core layer.
The forming process of the present invention will be described by taking the above-described flexible mold as an example of the use of the lower forming die. In the superplastic forming process, as shown in fig. 1, the lower core layer rib grids extrude the lower skin under the action of air pressure P1, wherein P1 is the pressure of the air filled in the second air passage on the core layer rib grids. And the pressure of the air between the ribs of the lower core layer on the lower skin is P2. The punches correspond to the core rib grids one by one, so that the punches and the skins on the punches bear the pressure P1, and the punches move under the action of the pressure P1. The skin at the cushion pan takes up pressure P2 and back stress F that results from the core rib cells pressing the skin. Under the action of P2 and back stress F, the skin at the buffer groove forms a protrusion along the inner wall of the buffer groove, and a groove appears on the surface of the skin. Typically, the size of the protrusion is determined by the back stress F. However, the back stress F is not sufficient to allow the size of the protrusion to continue to increase due to the presence of the buffer groove, thereby enabling the formation of an eliminable groove in the skin surface. Then, the punch is pushed by the pressure P1, so that the skins on both sides of the protruding part continue to move downwards, and the purpose of flattening the skins is achieved.
It should be noted that if the cushion grooves are rigid planes, under the action of P2 and the back stress F, the skin will form gaps on the side close to the lower core layer, and the gaps will also affect the performance of the product. Therefore, in the embodiment of the present invention, the buffer grooves are set to guide the P2 and F to form the eliminable grooves in the preset direction, and the grooves formed by the P2 and F are eliminated by pushing the movable forming plate 5 with the aid of the P1, that is, the process of generating the eliminable grooves-eliminating repeatedly in the forming process is realized by the buffer grooves 52, the punch 51 and the movable forming plate 5 being matched with each other under the conditions of P1, P2 and F until the forming is completed.
In the forming process, if the core rib grid is pressed against the skin at a rapid growth time, it is easy to form an indelible groove on the skin. In order to solve the problems, in the embodiment of the invention, the skin is preformed in advance, so that the skin is bowl-shaped, and enough growth space is reserved for the core layer rib grids in advance. This means that one more preformed mold needs to be prepared, which increases the complexity of the process and affects the accuracy of the device dimensions.
In order to solve the above technical problem, in the embodiment of the present invention, on the basis of the above mold, a limiting member is disposed in the closed chamber between the pressing plate 1 and the moving side of the movable forming plate 5. By the stopper, the maximum amount of movement of the movable forming plate 5 within the closed chamber can be restricted.
Although the embodiment of the present invention is applicable to a plurality of position-limiting members, for example, a slot or a cableway is disposed on a sidewall of the enclosed space, and the position of the position-limiting member is limited by the slot or the cableway, or a pluggable plug pin, a pluggable rib, or other structures are disposed on the sidewall of the enclosed space, so as to achieve the position-limiting function. However, in actual processes, the size of the mold is usually matched with the product and the process, and although the structure can achieve the limiting effect, the size of the mold can limit the implementation of the mode.
Preferably, the limit stop may limit the maximum movement of the movable forming plate 5 within the closed chamber by its own dimensions. The limiting member can be in a plurality of states, the height size of each state is different, illustratively, the height size of the limiting member comprises a first size and a second size, and when the limiting member limits the movement amount by the first size, the mold is used for performing the skin; when the limiting piece limits the moving amount by the second size, the die is used for preparing the titanium alloy four-layer structure. The limiting part achieves the limiting effect through the change of the size, and the size of the limiting part can be designed according to the size of the die, so that the die provided by the embodiment of the invention can better meet the process requirements.
Can be multiple state in order to realize the locating part, and the high dimension under every state is different, exemplarily, the locating part is formed for the different pitch arc of many radius of curvature meets, including the smooth crotch portion that meets of spherical segment portion and with spherical segment portion if the locating part, crotch portion includes cambered surface and lower cambered surface, the radius of going up the cambered surface is greater than the radius of cambered surface down, the spherical segment radius size is between last cambered surface radius and lower cambered surface radius, the locating part can be along the rotation of the axle that is located the centre of sphere position, rotation angle is different, the high dimension of locating part is different. In one position, the spherical segment part of the limiting part is abutted against the moving side of the movable forming plate 5, the arc line of the highest point of the upper arc surface of the hook part of the limiting part is tangent to the bottom surface of the pressing plate, the height dimension is the largest at the moment, the limiting part realizes the limit value of the minimum moving amount, in the other position, one side of the spherical segment part of the limiting part is abutted against the moving side of the movable forming plate 5, the height dimension of the limiting part is the radius of the spherical segment part, and the limiting part can realize the limit value of the maximum moving amount.
Specifically, embodiments of the present invention provide another lower mold assembly as shown in fig. 4-6, including the entire structure of the mold of fig. 3 and a stop 6. The limiting member 6 has two dimensions, wherein fig. 5 corresponds to a first dimension and fig. 6 corresponds to a second dimension. The lower mould is used for skin pre-forming when the limiting member 6 limits the movement of the movable forming plate 5 to a first size, and for preparing the lower half of the titanium alloy four-layer structure when the limiting member is in a second size. The invention realizes multiple purposes by the mode and simplifies the process for preparing the titanium alloy four-layer structure.
In addition, an embodiment of the present invention provides an upper mold assembly, which is structurally shown in fig. 2. It should be noted that the lower mold assembly is selected as a multi-purpose mold to accommodate the hot press forming process. In the hot press forming process, the working state of the hot press forming die on the hot press forming device is shown in fig. 7, and obviously, the lower die assembly is more suitable for a hot press forming scene at this time.
Based on the die, the embodiment of the invention provides a preparation method of a titanium alloy four-layer structure, which comprises the following steps:
step 1, selecting plates for high-temperature forming of a four-layer structure, namely an upper skin, a lower skin, an upper core layer and a lower core layer.
And 2, performing the upper skin and the lower skin respectively by using the lower forming die.
In the embodiment of the invention, the diffusion connection between the core layer rib grids and the rib grids on the upper skin and the lower skin is prevented, so that a smooth exhaust channel is ensured for gas between the core layer rib grids in the forming process. Before step 2 and after step 1, respectively arranging ribs on the upper skin and the lower skin, and coating solder resist on the ribs, wherein the ribs correspond to gaps among ribs of the core layer.
And 3, stacking the preformed upper skin, the preformed upper core layer, the preformed lower core layer and the preformed lower skin in sequence, and arranging a ventilation pipeline to obtain the component.
In the embodiment of the present invention, a total of three ventilation pipelines are required to be provided, as shown in fig. 8, which are:
a first vent line X is provided between the upper skin and the upper core layer,
a second vent line Y is arranged between the upper core layer and the lower core layer,
a third vent line Z is provided between the lower core layer and the lower skin.
Step 4, placing the component into a space formed by an upper forming die and a lower forming die, wherein the preformed upper skin is abutted with a punch of the upper forming die, and the preformed lower skin is abutted with the lower forming die;
In the embodiment of the invention, the diffusion connection temperature is the diffusion connection temperature, after the whole body is heated to the diffusion connection temperature, pressure is firstly applied to the first vent pipeline and the third vent pipeline and heat preservation is carried out, so that the upper core layer and the lower core layer are tightly attached, after the diffusion connection is finished, the whole body is heated to the superplastic forming temperature, and air pressure is continuously applied to the air inlet second vent pipeline.
To illustrate the feasibility of the above solution, the present invention provides the following embodiments:
example 1
The embodiment provides a high-temperature forming flexible die of a titanium alloy four-layer structure, which comprises a pressing plate 1, countersunk head screws 2, springs 3, a fixed forming plate 4 and a movable forming plate 5. The fixed forming plate 4 is connected to the platen 1 to form a chamber, the movable forming plate 5 is located at its moving side in the chamber, and the movable forming plate 5 is provided with punches 51 and buffer grooves 52 alternately distributed on its forming surface side. The fixed forming plate 4 is a cylindrical structure with a stepped hole and has a small-diameter section and a large-diameter section, the movable forming plate 5 is in a piston shape and comprises a head end and a rod end, the diameter of the head end is larger than that of the rod end, and the rod end is provided with punches 51 and buffer grooves 52 which are alternately distributed. The punch 51 and the buffer groove 52 of the movable forming plate 5 pass through the stepped hole, and the moving side of the movable forming plate 5 is lapped on the limit step to limit and fix the movable forming plate 5. Under the combined action of the forming pressure and the spring, the head end of the movable forming plate 5 moves along the cylinder wall of the large-diameter section of the fixed forming plate 4, and the rod end moves together, wholly or partially, to the large-diameter section of the fixed forming plate 4.
The pressure plate is provided with a counter bore and a high-temperature spring mounting seat so as to facilitate the mounting of the high-temperature spring and the fixation of the pressure plate. Each small punch on the movable forming plate corresponds to each rib grid for the superplastic forming of the titanium alloy four-layer structure so as to apply proper pressure at the corresponding position, and the middle gap part can reserve a forming space for the superplastic forming skin so as to eliminate the space in the subsequent forming.
The principle of the forming die is as follows: under the action of air pressure loading and a high-temperature spring in superplastic forming, a titanium alloy four-layer structure product is slowly formed under the guidance of a movable molded surface, and due to inevitable extrusion force between ribs and back pressure between a core layer and a skin, the skin is formed in the die, and a groove which can be eliminated and protrudes outwards is formed as shown in figure 4. The outwardly projecting groove is maintained only at a low height because the clearance in the mould is small enough so that the forming force F required to fully form the groove is large and the compression force between the ribs is not sufficient to resist the forming force F. When the skin is completely attached to the mold, the removal of the groove and the surface flattening effect can be finally realized due to the disappearance of the back pressure and the reaction force of the surface of the mold.
Example 2
The embodiment provides a superplastic forming die assembly which comprises an upper forming die, a lower forming die, an upper forming die and a lower forming die.
The upper forming die can be the forming die shown in fig. 3, and the lower forming die can be the forming die shown in fig. 3, in which case, the existing hot-press forming die can be used for performing the upper and lower skin preforming.
The upper forming die may be the one shown in fig. 3 and the lower forming die may be the one shown in fig. 4, in which case the lower forming die may be used for the upper and lower skin preforming.
The upper forming die may be the one shown in fig. 4, and the lower forming die may be the one shown in fig. 4, in which case, the upper and lower skin preforms may be performed using the upper or lower forming die.
When the forming mold shown in fig. 4 is used, a pair of cam structures is newly added, so that the mold can be used as an upper skin preforming lower mold and a lower skin preforming lower mold after the cam structures fix the movable forming plate surface (see fig. 4), and can be used as a superplastic forming mold when the cam structures are loosened (see fig. 6).
Taking basic units of superplastic diffusion forming with a four-layer structure as an example, the forming method adopting the forming die shown in fig. 4 comprises the following steps: selecting plates for forming a four-layer structure at high temperature, wherein the plates are respectively an upper skin, a lower skin, an upper core layer and a lower core layer; fixing a forming lower die into a hot-pressing die by using a cam, and forming upper and lower skins by using the die and a hot-forming upper die to preliminarily obtain a basic outline of the skin; in order to prevent the forming surface materials from mutually diffusing, solder resists are coated on the rib grids of the skin and the core layer and the vent holes; stacking the four-layer plates according to an upper skin, an upper core layer, a lower core layer and a lower skin in sequence, welding the vent pipeline to the position shown in the figure 8, and sealing and welding the periphery of the vent pipeline; placing a cam for forming the lower die at a loosening position, then loading the obtained component into an upper die and a lower die for superplastic forming and installing the components on a thermoforming machine, heating the whole to a diffusion connection temperature, and applying pressure between an upper skin and an upper core layer and between a lower skin and a lower core layer to complete diffusion connection; and applying pressure between the upper core layer and the lower core layer to realize superplastic forming of the rib grids of the core layer.
Example 3
The embodiment provides a flexible forming die and a forming method for a titanium alloy four-layer structure high-temperature forming product; the material of the part is TA15 titanium alloy, the external dimension of the part is 300mm multiplied by 300mm, and the internal structure of the part is shown in figure 9. In the present forming method, the titanium alloy four-layer structure high-temperature forming flexible mold shown in fig. 4 is used as the lower forming mold, and the titanium alloy four-layer structure high-temperature forming flexible mold shown in fig. 3 is used as the upper forming mold. The specific method steps of this example are as follows:
step 1, blanking of blanks.
And (3) blanking the flat plate by using a laser cutting machine, wherein the blanking size is 300mm multiplied by 300mm, and the thickness of the upper skin plate and the lower skin plate is 1.6 mm. And after blanking is finished, removing slag around the plate by using an angle grinder.
And 2, carrying out hot-pressing preforming on the upper skin and the lower skin.
In order to improve the quality of core layer superplastic forming, the upper skin and the lower skin are preformed by hot pressing. It is first necessary to place the cam (stopper) of the lower forming die in the chucking position (to be stopped by the first dimension) and to mount the lower forming die to the thermoforming machine. And then carrying out alkali-disintegrating acid washing on the machined pretreated upper skin and the machined pretreated lower skin so as to remove surface oil stains and facilitate the adhesion of protective coatings. And then uniformly spraying thermal protection coatings on the surfaces of the upper skin and the lower skin after the alkali-disintegration and acid-washing so as to lubricate and protect the surfaces in the thermal forming process. And finally, placing the skin into a thermoforming machine for preheating for 5 minutes and then forming, and maintaining the pressure for 10 minutes after forming is completed to obtain the basic contour of the skin. After the upper and lower skins are pre-formed, the deformation amount of the upper and lower skins is [ 60%, 80% ] of the final deformation amount.
And 3, coating a solder resist.
Solder resist is applied to the core layer air passages and the forming parts to prevent diffusion bonding at high temperatures. The inner surface of the core layer is coated with strippable paint, and then the inner surface of the core layer is stripped after a corresponding shape is carved by a blade at the shadow position in figure 2 (the painted part is ensured to be corresponding to the rib grids of the core layer). And finally, uniformly spraying the prepared solder resist on the inner surface of the core layer, and removing the rest strippable paint after the solder resist is completely dried.
And 4, sealing and welding.
The upper core layer is first welded to the lower core layer and the second vent line is welded at the location of the air inlet as shown in fig. 8. And welding the upper skin, the lower skin, the sealed upper core layer and the sealed lower core layer together, welding a first ventilation pipeline between the upper skin and the upper core layer, and welding a third ventilation pipeline between the lower skin and the lower core layer.
And 5, diffusion bonding and superplastic forming.
It is first necessary to set the cam (stopper) of the lower mold to the release position (to be stopped by the second dimension) and to mount the upper and lower superplastic forming dies to the thermoforming machine. And putting the welded whole into a die, and putting the die into a hot press to integrally heat the die to the diffusion bonding temperature. And then applying 0.1MPa of air pressure into the first ventilation pipeline and the third ventilation pipeline and preserving heat for 2 hours to ensure that the core layer is tightly attached, thereby being beneficial to finishing the diffusion connection of the core layer. After the diffusion connection is completed, the whole plate is heated to the superplastic forming temperature, and air pressure is continuously applied to the air inlet second air passage, so that the superplastic forming/diffusion connection process of the whole plate is completed.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.
Claims (9)
1. The utility model provides a titanium alloy four-layer structure high temperature flexible mould that takes shape which characterized in that includes: a press plate, a spring, a fixed forming plate and a movable forming plate;
the fixed forming plate and the pressing plate form a closed chamber;
the movable forming plate is mounted on the fixed forming plate, punches are arranged on the movable forming plate, buffer grooves are formed among the punches, the punches correspond to the core rib grids of the titanium alloy four-layer structure one by one, and the movable forming plate can move relative to the fixed forming plate;
and in the closed chamber, one end of the spring is connected with the pressure plate, and the other end of the spring is connected with the movable forming plate.
2. The mold of claim 1, further comprising: a limiting member;
the locating part is arranged in the closed cavity and is arranged between the pressure plate and the movable forming plate.
3. The mold according to claim 2,
the limiting piece comprises a first size and a second size;
when the limiting piece limits the movable forming plate to move by the first size, the mould is used for preforming the skin of the titanium alloy four-layer structure;
when the limiting piece limits the movable forming plate to move in the second size, the die is used for preparing the titanium alloy four-layer structure.
4. A mold assembly, comprising: an upper forming die;
the upper forming die adopts the die of claim 1.
5. The mold assembly of claim 4, further comprising: a lower forming die;
the lower forming die is the die set forth in any one of claims 1 to 3.
6. A method for preparing a titanium alloy four-layer structure, which is based on the die assembly of claim 4 or 5, and comprises the following steps:
step 1, selecting plates for high-temperature forming of a four-layer structure, namely an upper skin, a lower skin, an upper core layer and a lower core layer;
step 2, performing the upper skin and the lower skin respectively by using a lower forming die to obtain a preformed upper skin and a preformed lower skin;
step 3, stacking the preformed upper skin, the upper core layer, the lower core layer and the preformed lower skin in sequence, and arranging a ventilation pipeline to obtain a component;
step 4, the component is arranged in a space formed by an upper forming die and a lower forming die, wherein the preformed upper skin is abutted with a punch of the upper forming die, and the preformed lower skin is abutted with a punch of the lower forming die;
step 5, mounting the component, the upper forming die and the lower forming die on a hot forming machine, and heating to a diffusion bonding temperature; applying pressure to the preformed upper skin, the space between the upper core layers and the preformed lower skin and the space between the lower core layers through the vent pipeline to enable the upper core layers and the lower core layers to complete diffusion connection; and applying pressure between the upper core layer and the lower core layer through the vent pipeline to realize superplastic forming of the rib grids of the core layer.
7. The method of claim 6, wherein after step 1 and before step 2, the method further comprises:
respectively arranging ribs on the upper skin and the lower skin, and coating solder resist on the ribs;
the ribs correspond to gaps among the ribs of the core layer.
8. The method of claim 7, wherein step 3 comprises:
arranging a first vent line between the upper skin and the upper core layer;
a second vent pipeline is arranged between the upper core layer and the lower core layer;
and a third air through pipeline is arranged between the lower core layer and the lower skin.
9. The method of claim 8, wherein the step 5 comprises:
after the whole body is heated to the diffusion connection temperature, pressure is applied to the first ventilation pipeline and the third ventilation pipeline and heat preservation is carried out, so that the upper core layer and the lower core layer are tightly attached; after the upper core layer and the lower core layer are in diffusion connection, integrally heating to a superplastic forming temperature, and continuously applying air pressure to a second air passage; the ensemble is indicative of the upper skin, the upper core layer, the lower core layer, the pre-formed lower skin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111083106.9A CN113751570B (en) | 2021-09-15 | 2021-09-15 | Titanium alloy four-layer structure forming die, die assembly and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111083106.9A CN113751570B (en) | 2021-09-15 | 2021-09-15 | Titanium alloy four-layer structure forming die, die assembly and preparation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113751570A CN113751570A (en) | 2021-12-07 |
| CN113751570B true CN113751570B (en) | 2022-09-02 |
Family
ID=78795851
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111083106.9A Active CN113751570B (en) | 2021-09-15 | 2021-09-15 | Titanium alloy four-layer structure forming die, die assembly and preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113751570B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114713699B (en) * | 2022-06-09 | 2022-09-30 | 太原理工大学 | Metal bipolar plate gas expansion forming device and process based on pulse current assistance |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012173512A1 (en) * | 2011-06-15 | 2012-12-20 | Учреждение Российской Академии Наук Институт Проблем Сверхпластичности Металлов Ран (Ипсм Ран) | Method for manufacturing a hollow fan blade |
| CN106271439A (en) * | 2016-08-30 | 2017-01-04 | 北京普惠三航科技有限公司 | The superplastic forming of the heat-resisting eyelid covering of titanium alloy/diffusion joint forming method |
| KR20170078448A (en) * | 2015-12-29 | 2017-07-07 | 주식회사 성우하이텍 | Device for Multi forming |
| CN107470436A (en) * | 2017-08-07 | 2017-12-15 | 北京航星机器制造有限公司 | A kind of alloy three-decker surface grooves control method |
| CN108407332A (en) * | 2018-03-23 | 2018-08-17 | 航天材料及工艺研究所 | A kind of composite material grid stressed-skin construction part compression-moulding methods |
| CN109158842A (en) * | 2018-10-31 | 2019-01-08 | 北京普惠三航科技有限公司 | The processing technology of aerofoil is reinforced in a kind of titanium alloy lightweight |
| CN109986805A (en) * | 2019-05-01 | 2019-07-09 | 西北工业大学 | For guaranteeing multiple flexible-mould assisted forming method of the material with muscle siding Varying-thickness covering and rib profile forms |
| CN110340244A (en) * | 2019-07-22 | 2019-10-18 | 北京航星机器制造有限公司 | A kind of four-layer structure substep superplastic forming-diffusion connection method |
| CN111531335A (en) * | 2020-05-23 | 2020-08-14 | 北京普惠三航科技有限公司 | Multilayer structure and processing method thereof |
| CN111804786A (en) * | 2020-05-22 | 2020-10-23 | 北京卫星制造厂有限公司 | Integrated method for step-by-step progressive hot forming and hot sizing of thin-wall integral wall plate with ultrahigh reinforcing ribs and oversized flanges |
| CN112975287A (en) * | 2021-02-23 | 2021-06-18 | 哈尔滨工业大学 | Superplastic deformation/diffusion connection forming technology for wavy hollow skin structure part |
-
2021
- 2021-09-15 CN CN202111083106.9A patent/CN113751570B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012173512A1 (en) * | 2011-06-15 | 2012-12-20 | Учреждение Российской Академии Наук Институт Проблем Сверхпластичности Металлов Ран (Ипсм Ран) | Method for manufacturing a hollow fan blade |
| KR20170078448A (en) * | 2015-12-29 | 2017-07-07 | 주식회사 성우하이텍 | Device for Multi forming |
| CN106271439A (en) * | 2016-08-30 | 2017-01-04 | 北京普惠三航科技有限公司 | The superplastic forming of the heat-resisting eyelid covering of titanium alloy/diffusion joint forming method |
| CN107470436A (en) * | 2017-08-07 | 2017-12-15 | 北京航星机器制造有限公司 | A kind of alloy three-decker surface grooves control method |
| CN108407332A (en) * | 2018-03-23 | 2018-08-17 | 航天材料及工艺研究所 | A kind of composite material grid stressed-skin construction part compression-moulding methods |
| CN109158842A (en) * | 2018-10-31 | 2019-01-08 | 北京普惠三航科技有限公司 | The processing technology of aerofoil is reinforced in a kind of titanium alloy lightweight |
| CN109986805A (en) * | 2019-05-01 | 2019-07-09 | 西北工业大学 | For guaranteeing multiple flexible-mould assisted forming method of the material with muscle siding Varying-thickness covering and rib profile forms |
| CN110340244A (en) * | 2019-07-22 | 2019-10-18 | 北京航星机器制造有限公司 | A kind of four-layer structure substep superplastic forming-diffusion connection method |
| CN111804786A (en) * | 2020-05-22 | 2020-10-23 | 北京卫星制造厂有限公司 | Integrated method for step-by-step progressive hot forming and hot sizing of thin-wall integral wall plate with ultrahigh reinforcing ribs and oversized flanges |
| CN111531335A (en) * | 2020-05-23 | 2020-08-14 | 北京普惠三航科技有限公司 | Multilayer structure and processing method thereof |
| CN112975287A (en) * | 2021-02-23 | 2021-06-18 | 哈尔滨工业大学 | Superplastic deformation/diffusion connection forming technology for wavy hollow skin structure part |
Non-Patent Citations (1)
| Title |
|---|
| 超塑性成形/扩散连接空心结构设计和强度分析;刘鹏程等;《河北科技大学学报》;20111015(第05期);435-440 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113751570A (en) | 2021-12-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110666457A (en) | Preparation method of titanium alloy thin-wall lightweight flap part | |
| CN113751570B (en) | Titanium alloy four-layer structure forming die, die assembly and preparation method | |
| CN110434216B (en) | Integral liquid filling forming method for large annular lip piece | |
| CN110479832B (en) | Method and device for forming and compositely preparing coated magnesium alloy multilayer structural part | |
| CN109967588B (en) | Liquid filling forming method for aluminum alloy differential thickness tailor-welded blank | |
| CN109955042B (en) | Preparation method of titanium alloy hollow structure | |
| US20210197261A1 (en) | Method for Manufacturing Thin-Walled Metal Component by Three-Dimensional Printing and Hot Gas Bulging | |
| CN109623265B (en) | Precise machining method for complex thin-wall variable-thickness large opening cover | |
| CN115008127B (en) | Integrated manufacturing method for maintenance window on surface of aircraft body | |
| CN113770253B (en) | Titanium alloy four-layer structure forming die, die assembly and skin groove eliminating method | |
| CN109692911A (en) | A kind of large size toroidal shell part monolithic molding device and method | |
| CN113751590B (en) | Titanium alloy four-layer structure forming method and mold assembly | |
| CN113751569A (en) | Airplane hatch cover skin liquid filling forming method | |
| CN109127851A (en) | A kind of manufacturing process based on hydraulic aluminium alloy sheet part | |
| CN109202255B (en) | Three layers of hollow structural component of thin-walled and the method for controlling surface trench defect | |
| CN210497867U (en) | Poor thick tailor-welded blank hydroforming device of aluminum alloy | |
| CN115971628A (en) | Control method for superplastic forming diffusion connection triangular area fillet with titanium alloy four-layer structure | |
| CN114211202B (en) | Forming method of beneficial friction titanium alloy space lattice structure and mold used by forming method | |
| CN113926905B (en) | Superplastic forming die and forming method for variable-section titanium alloy shell part | |
| CN113787306B (en) | Flow control accurate thermal forming method for combustion chamber cap cover | |
| KR101228811B1 (en) | Mold for Hydro-Forming of Closed-Member and Method for Manufacturing Integration Parts using The Same, and Integration Parts | |
| US9849546B2 (en) | Method for manufacturing a hydraulic device | |
| CN108480924A (en) | A kind of forming method and molding machine of double panel structure part | |
| CN110899411A (en) | Bending forming system and method for knuckle | |
| CN211679442U (en) | Bending and forming system for knuckle |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |